Neurocognitive and clinical correlates of insight in schizophrenia

BACKGROUND: Schizophrenia is a heterogeneous disorder characterized by various symptom dimensions and neurocognitive deficits. Impairment of insight is a core clinical symptom of the disorder. There has been an increasing focus on neurocognition and insight in schizophrenia; although, many studies fail to control for premorbid cognitive status. MATERIALS AND METHODS: Schizophrenia patients (n = 60) selected for adequate background education were recruited from outpatient services of a tertiary care hospital and community care homes in Southern India. These patients were comprehensively assessed using a neurocognitive battery. Clinical assessments were done using the Positive and Negative Syndrome Scale (PANSS) and Schedule for the Assessment of Insight-expanded version (SAI-E). Partial correlation was performed to examine the relationship of insight with clinical and neurocognitive measures. Statistical significance was set at P = 0.004 (Bonferroni correction for 12 tests of association). Linear regression analysis was performed to examine the predictors of insight. RESULTS: The mean PANSS positive, negative, general psychopathology, and total scores were 14.2 ± 4.9, 17.4 ± 5.0, 34.3 ± 6.8, and 65.8 ± 13.9, respectively. Mean insight score (SAI-E) was 8.5 ± 2.9. In partial correlation done after controlling for IQ, significant negative correlations were observed between insight score and the Wisconsin Card Sorting Test (WCST) total errors (P = 0.001), WCST perseverative errors (P < 0.001). Insight scores had negative correlations with PANSS negative (P < 0.002) and total scores (P < 0.002). WCST perseverative errors were the primary predictor of insight in the regression analysis. CONCLUSION: Insight has a strong relationship with executive functioning in schizophrenia. This could indicate shared neurobiological substrates for insight and executive functioning.